1. Field of the Invention
The present invention relates to a coil resonant coupler for short distance wireless power communication, and a short distance wireless power transmitting apparatus comprising the same.
2. Description of the Related Art
Generally, portable apparatuses such as cellular phones, personal digital assistants (PDAs), portable multimedia players (PMPs), digital multimedia broadcasting (DMB) terminals, MP3 players, or laptop computers may not use general household power, such that the portable apparatuses are mounted with a one-time battery or a rechargeable battery.
In a charger for charging the battery of the portable apparatus with electricity, a terminal supplying scheme of receiving the electricity from a general power supply and supplying power to a battery pack of the battery through a power supplying terminal is known in the related art. However, when the power is supplied in the terminal supplying scheme, if the charger and the battery are connected to or disconnected from each other, the respective terminals may have different potential differences and may generate an instantaneous discharge phenomenon. Therefore, foreign materials which may have collected at the terminals create a risk of a fire. In addition, self-discharge into the environment due to moisture or the like may deteriorate a lifespan and performance of the charger and the battery.
In order to solve these problems in the terminal supplying scheme, a contactless charger has been developed. In the contactless charger according to the related art, when a terminal, in which a battery to be charged is embedded, is positioned on a primary coil of the contactless charger, the battery is charged with electricity by a secondary coil of the battery. That is, the secondary coil charges electricity of an electromotive force induced by a magnetic field generated in the primary coil.
However, the contactless charger according to the related art may charge the battery only if a wireless power receiving apparatus is significantly close to the charger.
In order to solve this problem, short distance wireless power communication systems have been developed. Among these short distance wireless power communication systems, a magnetic resonance type wireless power communication system in which less or more directed electromagnetic waves are generated has been suggested, in order to increase efficiency of power transmission.